Electric furnace for treating gases



B. THOMAS. ELECTRIC FURNACE FOR TREATING GASES.

APPLICATION FILED APR.30, 1917. F

Patented. Feb. 8, 192-1.,

3 SHEETS SHEET I.

I awum vlio'c Brzzzzo 73502223 5.

B. THOMAS. ELECTRIC FURNACE FOR TREATING GASES. 7

APPLICATION FILED APR.3 I I L fiiffigu I I Patented Feb. 8,1921. k I 3 s EEEE S SHEE T 2 IN VE N TOR A TT ORNE Y B. THOMAS.

ELECTRIC FURNACE FOR TREATING GASES.

APPLICATION FILED APR.30, I917.

' lfifiT/fii n I I Patented Feb. 8, 1921.

' 3 SHEETSSHEET 3.

. INVENTIOR 11220 7 0222a improvements in the construction of the .iBRUN-Q 'rnouas, orjs'nii'r'rLE, .wA-snrNe'ro-n;

anaemic 'runnacr. Eon 'rnnarme cases.

' Specification of Letters Patent.

Application filed a iiaaieiv," Serial No. 165,553.

To all whom itmdy concern: Be it known that,I, BRUNO THoMas, a

citizen-of the United States, and. resident of the city. of Seattle, county of King, and

State of Washington, have invented cer-' tain new and useful Improvementsin Electric Furnaces for Treating Gases, of which the following is a specification,

- struction which is now most preferred loy- ."nace having air supply mechanism which pointed out in the claims.

naces wherein the transformation of gases is produced by the action of an electrical arc thereon, of which the more generally known application is for the purpose of the oxidation or fixation of atmospheric nitrogen. r

- -Th'e object of my invention is to improve the apparatus and methods employed to' --thereby decrease the cost' of production of a unit of the product.

My present invention comprises certain apparatus which impr'ov'ementswill be hereinafterdescribed and then part cularly In the accompanying drawings; shown myinvention in .the. form of con- Figure 1 is a vertical section through a furnace having the simplest construction. Fig. 2 is a like section through a furnaceusing horn electrodes.

Fig. 3 is a vertical sect on through a furintroduces a portion of the air at the'center but having a whirling movement which throws it outward through the arc.

Fig. 4 is like Fig; 3 except that; all the air is introduced at the center and is given a cyclonic movement' before introduction.-

. Fig 5 is similar to F ig.- 4;.butwith the use of horn electrodes .Wh-lC h are spaced about the air inlet.

shown in Fig. 5'. l

Fig. 7 is like Fig. 5 .e'xecept that the horn electrodes are twisted in the helicesor spirals.

, Fig.8 is a vertical section and Fig. 9 a

plan, .partly in broken section, showing one preferred type of furnace construction.

In the more commontypes of'furnas as hitherto employed for oxidation of:gases underthe influence, .of"' the electrical arc, it has been customary to form a single-elec- 's-rical arc in, or adj acentto, the central axis of furnacealongstable arc is. formed.

action of the are upon the air; is ,niostintimate ,and ,efiective'upon thatpart which My invention relates to electrical fur-- has been forced from the outside inw d methods and apparatus. I

I- have form of conical ducing' a less dense central core, of air in;

which the arc is maintained. In this has. been lower than it should be;

[Pat nted Feb. 8, 1921.

In my present invention I lo rality together to forma composite. arc of increased surface and form this composite arc in such shape and pass the air, or-ga'ses,

through this are in such manner, as secures a more effective oxidizing action of'the arc upon the air than is'secured of' electrical are which are merged in I byfthe former-l In the form of furnace-shown in'Fig. 2, I

I employ a series'of electrodes, 2,, in the form of horn electrodes, these being in numbercorrespo'nding with the number of "phases'in the current employed, and'being'grouped' about a central point or axis.

he air is supplied undera pressure which IS IIliOI'G .or less greater thanthat in the furnace-chamber 1, entering through a passage 3 which discharges from between the electrodes.- -The reduction of pressure on entering the furnace, causes a; lateral expansion, this being assisted 'by the expanding mouth 11-, when such a mouth is used. In consequen ce, the air is brought into intimate contactwith the arc.

. 'In-the furnace shown in Fig. 2, arcs are formed joining the electrodes 2 and may also be formed between these electrodes and a common return -'electrode, if, such. be enitending from the air inlet pipe 3l, which ployed. Inthe furnace shown in Fig. 1, a single phase current is used, the are ex Fig, 6 is a plan viewof the construction forms one electrode, to the pipe 10, which forms the other electrode.

In the furnace,.as shown in Fig. 3, the electrode 20 has the air inlet '3 therein and also a dome-shaped circular chamber 21 into which the air is supplied from a passage 22, which discharges tangentially of the chamber 21, thereby producing a whirling movement in the air. As the air is' forced to the center in order to escape through-the discharge nozzle 3, the rate of whirling is intensified and it is discharged intothe furnace whirling at a' high? rate: As it escapes-from"thenozzle 3 it is freed from restraint, and, due to the'centrifugal tendency produced by-this whirling action, tends very strongly to spread radially, or from the central axis .of'the'furnace; to

ward its outer wall. In doin'gfthis'it must pass through the arcs which extend between the electrodes.

"shows a supplemental air supply-entering In addition-to the above" features, .Fig. 3

the furnace through. the annular'op'ening .12 existing between the electrode 20 and the wall of jthe furnace. This permits the supply of an additional volume of air which is'caused to impinge directly upon the arcs --which .have been expanded by the action of the furnace shown in Fig. 5.- The furnace ing water therein.

of'the air entering through the'nozzle 3.

, v v The furnace shown in Fig. v4 is the same -20 in construction and action as that of Fig.

air inlet 12.

The furnace shown-in 3, except for the omission of-the annular Fig. 5 differs from thatfshown in Fig. .4, onlyin having a sharper angled conical mouth '11' and-in using horn electrodes 2, .to which a multi-' phase current is applied. 'It is also-like that of. Fig. 2 except forthe use of the preliminary chamber 21 in which the whirling effect is given the air. Fig.6 shows-a plan view of Fig. 7 is like that of Figs. 5-and 6 with the horn electrodes 23 curvedinto conical helices.

In the furnace shown in 8 and 9, the

preliminary air chamber 21 is used to give" the 'air a whirling movement before its introduction to the furnace chamber.

.The electrodes consist of tubular members 2 which lie flat upon the conical bottom of the} chamber. These are, keptco'ol fb'y circulat- In this furnace, the length of the furnace relative to its diameter is small. I have also shown-fa common-return electrode 4, thisbeing hollow and water cooled. It is of less diameter than the furnace and centrallyplaced, thusleaving an annular dis' charge opening. The are fills this furnace chamber, The air passes through the arc and is then" immediately discharged .into cooling passages, thus much facilitating cooling ofthe combined gases-before sufli-L cient time has elapsed to permit dissociation.

tendencies to have any material efiect.

Itis well known that combination of the .gases under the action of the electricyarc takes plac with greater rapidity at high temperatures than at lower. It is also well known that dissociation of the, gases also acts more'rapidly at high temperatures.

In the ordinary furnace using long arcs inefiiciency.

forming terminals 0 -nary receiving chamber.

' 'chamber.

. Signed at Seattle, Washington,this 25th the time of' exposure to the high tempera- 'tures of thearc, during the passage through- =-the furnace,"is so much greater .than th t' "necessary for dissociation to take place,.that only ass nall'part of the latter part of this 1. A furnace for electrically combining gases having an arc forming chamber, a preliminary receiving compartment for the gasesinto which the gases are introduced tangentially to thereby roduce a whirling movement therein, an air conduit connecting'said two chambers and positioned axially of each, and electrodes within the .arc formingchamber "and grouped about the air inlet conduit.

2. In a furnace for electrically combining gases,ian arc-forming chamber having a central. air inlet, a olurality .of electrodes i a multiphase current and grouped about said air inlet, means for giving the air av whirling movement before entering said air inlet, said means comprism a ,prellmlnary receivlng chamber connecting centrally with and discharging through said air inlet, and means for introducing air tangentially into said prelimi- .3. A furnace 'for electrically combining gases having an are forming chamber, a prelimlnary receiving compartment for the 1 gases into which the'gases are introduced in afmanner to produce a cyclonic whirling movementtherein, an air COIN uit connectingsald two chambers and elec rodes w1th1n the are forming chamber and grouped about the said air-inlet conduit.

- 4;. An electric furnace of the type named having a centrally placed air inlet at one end and an annular air .discharge openingat the other end, a plurality of electrodes. entering through said air inlet,,extending outwardly as a loop and returning to-and passing out through said air inlet,' and an electrodes, placed within the annular exit opening at the other end of the arcing day of April, 1917.-

' BRUNQTHOMASQ,

' electrode complemental to the first-named- 

